The reverse lights did not work when purchased new. The dealer found burnt wiring and had to replace the harness. Car was out for a month. I thought the dealer should have replaced the car.
Replaced rear bearings at 95000 miles for a total cost of $600.
Battery was replaced at 90000 miles (five years later)
Currently on third set of tires and brakes.
Although functional, the LED display is intermittently partial, sometimes get bogus 'check engine' light.
Spilled soft drinks makes the radio and A/C controls sticky, especially at sub-zero temperatures.
Despite the first electrical problem with the car, I think it has held up very, very well in the harsh conditions of New York City metro area.
I have found this to be a very low maintenance car.
At 100K, the performance is like new and the car never disappoints me.
The interior has no rattles and the leatherette is only now showing very minor signs of wear. My five and 2 year old have tried, but have not yet been able to break anything in the rear.
Update at 118,000 miles:
- New set of Tires (nokian WR)
- Finally replaced timing belt
- $400 of work to replace Tie-Rods and Lower control arms - this is apparently a problem for A4s.
Now buying an Audi A3 Sportback 2.0T 6Man, Wife is keeping the old A4
Update at 150K.
I drove the car for a 100 miles. Still not rattles, turbo pulls strong. Computer Display is completely messed up (but its not critical). Car makes a funny pumping noise after cold start, but goes away after 30secs. All engine components: alternator, starter, exhaust, pumps, coil packs all still original from 2000.
Note: A Comments RSS Feed 
is available. New comments appear in the Members Area before the main site